COMBINING RAIN GAUGES WITH SATELLITE MEASUREMENTS FOR OPTIMAL ESTIMATES OF AREA-TIME AVERAGED RAIN RATES Academic Article uri icon

abstract

  • The problem of optimally combining data from an array of point rain gages with those from a low Earthorbiting satellite to obtain spacetime averaged rain rates is considered. The mean square error due to sampling gaps in spacetime can be expressed as an integral of a filter multiplied by the spacetime spectral density of the rain rate field. It is shown that for large numbers of gages or large numbers of overpasses the two estimates can be regarded as orthogonal in the sense that the optimal weighting is the same as for independent estimators, i.e., the weights are inversely proportional to the error variances that would occur in the singlecomponent case. The result involving point gages and satellite overpasses appears to hold under quite general conditions. The result is interesting since most other design combinations do not exhibit the orthogonality property. Copyright 1991 by the American Geophysical Union.

published proceedings

  • WATER RESOURCES RESEARCH

author list (cited authors)

  • NORTH, G. R., SHEN, S., & UPSON, R. B.

citation count

  • 21

complete list of authors

  • NORTH, GR||SHEN, SSP||UPSON, RB

publication date

  • October 1991